The hair cycle normally consists of growing, resting and falling hairs and there is a delicate balance between these stages of hair cycle. Normally hair should re-grow but if it is not happening, you should consider seeing a dermatologist.
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Few weeks of hair fall usually relates to a acute cause or sometimes the beginning of a chronic cause. Did you have an illness in preceding few months like a typhoid, malaria or did you undergo a surgery. Are there any acute stressors, any unusual problems? If there are so, you may be having a condition called telogen effluvium ,and usually settles in few months time